P NOT TO SCALE 15 m 13 m R O 18 m Figure 1 Figure 1 shows triangle PQR with PQ = 15 metres, PR = 13 metres, QR = 18 metres and angle QPR = 0. Find the size of 0, giving your answer in degrees and to 3 significant figures. [4] In this question: 1 mark will be given for the correct use of significant figures